A conventional golf club head, especially a so-called wood club head, of metal, was made from welding two or three metal pieces to construct a hollow head. For example, a wood club head can be constructed from a bottom, a crown and a face, or it also can be constructed from a crown and a bottom with a face thereon. Except for metal, more and more wood heads were made of composite material, such as carbon composite, which has capacities of lighter weight, higher strength and well elasticity etc. But, there were some unsolved problems when manufacturing the golf club heads of composite material.